package com.guodi.model.utils;

import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Vector;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

/**
 * @Author eve
 * @Date 2021/7/15 16:11
 */
public class ZipUtil {
    private static final int BUFFER_SIZE = 2 * 1024;

    /**
     * 压缩成ZIP 方法1
     *
     * @param srcDir           压缩文件夹路径
     * @param out              压缩文件输出流
     * @param KeepDirStructure 是否保留原来的目录结构,true:保留目录结构;
     *                         false:所有文件跑到压缩包根目录下(注意：不保留目录结构可能会出现同名文件,会压缩失败)
     * @throws RuntimeException 压缩失败会抛出运行时异常
     */
    public static void toZip(String srcDir, OutputStream out, boolean KeepDirStructure) throws RuntimeException {
        long start = System.currentTimeMillis();
        ZipOutputStream zos = null;
        try {
            zos = new ZipOutputStream(out);
            File sourceFile = new File(srcDir);
            compress(sourceFile, zos, sourceFile.getName(), KeepDirStructure);
            long end = System.currentTimeMillis();
            System.out.println("压缩完成，耗时：" + (end - start) + " ms");
        } catch (Exception e) {
            throw new RuntimeException("zip error from ZipUtils", e);
        } finally {
            if (zos != null) {
                try {
                    zos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * 压缩成ZIP 方法2
     *
     * @param srcFiles 需要压缩的文件列表
     * @param out      压缩文件输出流
     * @throws RuntimeException 压缩失败会抛出运行时异常
     */
    public static void toZip(List<File> srcFiles, OutputStream out) throws RuntimeException {
        long start = System.currentTimeMillis();
        ZipOutputStream zos = null;
        try {
            zos = new ZipOutputStream(out);
            for (File srcFile : srcFiles) {
                byte[] buf = new byte[BUFFER_SIZE];
                zos.putNextEntry(new ZipEntry(srcFile.getName()));
                int len;
                FileInputStream in = new FileInputStream(srcFile);
                while ((len = in.read(buf)) != -1) {
                    zos.write(buf, 0, len);
                }
                zos.closeEntry();
                in.close();
            }
            long end = System.currentTimeMillis();
            System.out.println("压缩完成，耗时：" + (end - start) + " ms");
        } catch (Exception e) {
            throw new RuntimeException("zip error from ZipUtils", e);
        } finally {
            if (zos != null) {
                try {
                    zos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * 递归压缩方法
     *
     * @param sourceFile       源文件
     * @param zos              zip输出流
     * @param name             压缩后的名称
     * @param KeepDirStructure 是否保留原来的目录结构,true:保留目录结构;
     *                         false:所有文件跑到压缩包根目录下(注意：不保留目录结构可能会出现同名文件,会压缩失败)
     * @throws Exception
     */
    private static void compress(File sourceFile, ZipOutputStream zos, String name, boolean KeepDirStructure)
            throws Exception {
        byte[] buf = new byte[BUFFER_SIZE];
        if (sourceFile.isFile()) {
            // 向zip输出流中添加一个zip实体，构造器中name为zip实体的文件的名字
            zos.putNextEntry(new ZipEntry(name));
            // copy文件到zip输出流中
            int len;
            FileInputStream in = new FileInputStream(sourceFile);
            while ((len = in.read(buf)) != -1) {
                zos.write(buf, 0, len);
            }
            // Complete the entry
            zos.closeEntry();
            in.close();
        } else {
            File[] listFiles = sourceFile.listFiles();
            if (listFiles == null || listFiles.length == 0) {
                // 需要保留原来的文件结构时,需要对空文件夹进行处理
                if (KeepDirStructure) {
                    // 空文件夹的处理
                    zos.putNextEntry(new ZipEntry(name + "/"));
                    // 没有文件，不需要文件的copy
                    zos.closeEntry();
                }
            } else {
                for (File file : listFiles) {
                    // 判断是否需要保留原来的文件结构
                    if (KeepDirStructure) {
                        // 注意：file.getName()前面需要带上父文件夹的名字加一斜杠,
                        // 不然最后压缩包中就不能保留原来的文件结构,即：所有文件都跑到压缩包根目录下了
                        compress(file, zos, name + "/" + file.getName(), KeepDirStructure);
                    } else {
                        compress(file, zos, file.getName(), KeepDirStructure);
                    }
                }
            }
        }

    }

	/**
	 * @描述: 多文件打包下载
	 * @入参:
	 * @出参:
	 * @作者: zxs
	 * @日期: 2022/11/8 17:13
	 **/
	public static String zipDownload(String filePath, HttpServletResponse response) throws IOException {
		String sourceFilePath = filePath;
		String destinFilePath = filePath;
		String fileName = zipFiles(sourceFilePath, destinFilePath);
		File file = new File(destinFilePath + File.separator + fileName);
		response.setHeader("Content-disposition", "attachment;filename=" + fileName);
		if (file.exists()) {
			FileInputStream fis = null;
			BufferedInputStream bis = null;
			OutputStream out = response.getOutputStream();
			try {
				fis = new FileInputStream(file);
				bis = new BufferedInputStream(fis);
				byte[] bufs = new byte[1024 * 10];
				int read = 0;
				while ((read = bis.read(bufs, 0, 1024 * 10)) != -1) {
					out.write(bufs, 0, read);
				}
			} catch (FileNotFoundException e) {
				e.printStackTrace();
			} finally {
				if (bis != null) {
					bis.close();
				}
//				if (out != null) {
//					out.close();
//				}
				File zipFile = new File(destinFilePath + File.separator + fileName);
				if (zipFile.exists()) {
					zipFile.delete();
				}
			}
		} else {
			return "文件压缩失败";
		}
		return "下载成功";
	}

	/**
	 * 压缩文件到指定文件夹
	 *
	 * @param sourceFilePath 源地址
	 * @param destinFilePath 目的地址
	 * @author: zxs
	 * @date: 2022/11/8 17:20
	 */
	public static String zipFiles(String sourceFilePath, String destinFilePath) {
		File sourceFile = new File(sourceFilePath);
		FileInputStream fis = null;
		BufferedInputStream bis = null;
		FileOutputStream fos = null;
		ZipOutputStream zos = null;
		SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
		String fileName = dateFormat.format(new Date()) + ".zip";
		String zipFilePath = destinFilePath + File.separator + fileName;
		if (sourceFile.exists() == false) {
			System.out.println("待压缩的文件目录：" + sourceFilePath + "不存在.");
		} else {
			try {
				File zipFile = new File(zipFilePath);
				if (zipFile.exists()) {
					System.out.println(zipFilePath + "目录下存在名字为:" + fileName + ".zip" + "打包文件.");
				} else {
					File[] sourceFiles = sourceFile.listFiles();
					if (null == sourceFiles || sourceFiles.length < 1) {
						System.out.println("待压缩的文件目录：" + sourceFilePath + "里面不存在文件，无需压缩.");
					} else {
						//读取sourceFile下的所有文件
						Vector<File> vector = FileUtil.getPathAllFiles(sourceFile, new Vector<File>());
						fos = new FileOutputStream(zipFile);
						zos = new ZipOutputStream(new BufferedOutputStream(fos));
						byte[] bufs = new byte[1024 * 10];

						for (int i = 0; i < vector.size(); i++) {
							// 创建ZIP实体，并添加进压缩包
							ZipEntry zipEntry = new ZipEntry(vector.get(i).getName());//文件不可重名，否则会报错
							zos.putNextEntry(zipEntry);
							// 读取待压缩的文件并写进压缩包里
							fis = new FileInputStream(vector.get(i));
							bis = new BufferedInputStream(fis, 1024 * 10);
							int read = 0;
							while ((read = bis.read(bufs, 0, 1024 * 10)) != -1) {
								zos.write(bufs, 0, read);
							}
						}
					}
				}
			} catch (FileNotFoundException e) {
				e.printStackTrace();
				throw new RuntimeException(e);
			} catch (IOException e) {
				e.printStackTrace();
				throw new RuntimeException(e);
			} finally {
				// 关闭流
				try {
					if (null != bis) {
						bis.close();
					}
					if (null != zos) {
						zos.closeEntry();
					}
					zos.close();
				} catch (IOException e) {
					e.printStackTrace();
					throw new RuntimeException(e);
				}
			}
		}
		return fileName;
	}


}
